1 files changed, 3 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 1db9e55..e18503d 100644
--- a/Makefile
+++ b/Makefile
@@ -1,2 +1,4 @@
+history := -const "Exn.keepHistory true"
+
 def:
-	mlton -const "Exn.keepHistory true" cpp.mlb
+	mlton $(history) cpp.mlb